/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.fs.s3.common.utils;

import org.apache.flink.annotation.Internal;
import org.apache.flink.util.IOUtils;

import java.io.Closeable;
import java.io.IOException;
import java.io.OutputStream;

import static org.apache.flink.util.Preconditions.checkNotNull;

/**
 * An {@link OutputStream} that keeps track of its current length.
 */
@Internal
public final class OffsetAwareOutputStream implements Closeable {

	private final OutputStream currentOut;

	private long position;

	OffsetAwareOutputStream(OutputStream currentOut, long position) {
		this.currentOut = checkNotNull(currentOut);
		this.position = position;
	}

	public long getLength() {
		return position;
	}

	public void write(byte[] b, int off, int len) throws IOException {
		currentOut.write(b, off, len);
		position += len;
	}

	public void flush() throws IOException {
		currentOut.flush();
	}

	@Override
	public void close() {
		IOUtils.closeQuietly(currentOut);
	}
}
